1. Field of the Invention
This invention relates to a new belt tensioner as well as to new methods of making such a new belt tensioner and to methods of assembling such a new belt tensioner.
2. Prior art Statement
It is known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction including two pairs of volute springs, for instance see U.S. Pat. No. 4,309,174 to Sproul. Sproul further teaches frictional sliding contact between successive coils.
It is also known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction and damping means wherein the biasing force and the dampening force both decrease as the lever means moves in a belt tensioning direction, for instance see U.S. Pat. No. 4,473,362 to Thomey, et. al.
It is also known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction and frictional dampening means comprised of a pair of frictionally engaging parts and additional spring means for biasing one of said parts against the other of said parts. For instance, see U.S. Pat. Nos. 4,596,538 and 4,832,666 to Henderson, or U.S. Pat. Nos. 4,938,734, 5,030,172 and 5,035,679 to Green, et al.
It is also known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction and a damping washer engaging a cooperating surface and having an axial force component which supplies proportional damping. For instance, see U.S. Pat. No. 4,698,049 to Bytzek, et al.
It is also known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction and frictional dampening means comprised of a stack of interengaging pairs of frictionally engaging surfaces and having an axial force component which supplies proportional damping. For instance, see U.S. Pat. No. 4,689,037 to Bytzek.
It is also known to provide a belt tensioner construction having spring means for biasing a lever means in a belt tensioning direction and frictional dampening means comprised of a stack of interengaging pairs of frictionally engaging surfaces and having an axial force component which may be supplied by an additional spring means for biasing said surfaces against each other. For instance, see U.S. Pat. No. 4,689,037 to Bytzek.